Organic materials such as thermoplastic resins, thermosetting resins, natural or synthetic rubbers, mineral oils, lubricants, adhesives, paints and the like deteriorate due to an action of heat, oxygen and the like in production, in processing and in use, accompanied by decrease in strength property, change of flowability, coloration, decrease in surface physical property, and the like of the organic materials ascribable to a phenomenon such as molecule cut and molecule crosslinking, leading to remarkable deterioration of commercial value in some cases.
A polycarbonate which is one of thermoplastic resins is used generally in electric device housings, optical lenses, and building materials such as windowpane and the like because of excellent impact resistance, transparency, dimension stability and the like.
In patent document 1, as a stabilizer for a polycarbonate having a main repeating unit represented by the following formula:
(wherein, R1′, R2′, R3′ and R4′ represent each independently a hydrogen atom, alkyl group having 1 to 10 carbon atoms, aralkyl group or aryl group, and W represents an alkylidene group, cycloalkylene group, alkylene group substituted with an aryl group, oxygen atom, sulfur atom, sulfoxide group or sulfone group.), suggested is a silane type stabilizer of the following formula (A):
(wherein, R5′ to R7′ represent each independently a hydrogen atom, alkyl group having 1 to 20 carbon atoms, alkoxyl group having 1 to 20 carbon atoms or aryl group having 6 to 20 carbon atoms, or a silyl group of the following formula (B):
{wherein, X′ represents a single bond, oxygen atom, sulfur atom or alkylene group having 1 to 10 carbon atoms. Y1′ to Y3′ represent each independently a hydrogen atom, alkyl group having 1 to 20 carbon atoms, alkylsilyl group having 1 to 20 carbon atoms, alkylsiloxy group having 1 to 20 carbon atoms, aryl group having 6 to 20 carbon atoms optionally having a substituent, arylsilyl group having 6 to 20 carbon atoms, arylsiloxy group having 6 to 20 carbon atoms or siloxanyl group.}).
Patent document 1: JP-A No. 2001-247758